Product Description
Cummins 4988747 — Genuine Mechanical Fuel Transfer Lift Pump for 5.9L 12-Valve (P7100)
MPN: 4988747 | Also Known As: mechanical lift pump, fuel transfer pump, P7100 supply pump | Replaces: 3936316, 3936317 | Common Cross-Refs: 4944710, Bosch 0 440 020 047
Genuine Cummins camshaft-driven, piston-type fuel transfer pump with hand primer. Designed to supply low-pressure fuel to the P7100 injection pump on 1994–1998 Ram 5.9L 12-valve trucks. Built to OE specs for reliable starts, stable idle, and proper fuel delivery under load.
Features & Benefits
- OE piston-style pump for consistent supply pressure to the P7100.
- Hand primer simplifies priming after filter or line service.
- Direct-fit block mount using the factory spacer and gasket.
- Typical output ~25–35 PSI at idle for healthy fuel delivery.
- Durable Cummins build for long service life and easy starts.
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1994–1998 | 5.9L 12V (6BT) with P7100 | Ram 2500/3500 |
Industrial/Off-Highway: Used on various B/ISB Tier 2 and some C/ISC/6CTA applications. Verify by ESN before ordering.
Compatibility Notes:
- For 5.9L 12V P-pump trucks only (1994–1998). 1989–1993 (VE-pump) use a different diaphragm-style pump; 1998.5–2002 24V (VP44) use an electric lift pump; 2003+ common-rail use different systems.
- Requires spacer & gasket: use spacer 3914284 (’94–’98) and gasket 3939258 (’89–’98) at the mounting interface.
Specifications
- Type: Mechanical, piston-type fuel transfer (lift) pump
- Actuation: Camshaft eccentric (block-mounted)
- Typical Pressure: ~25–35 PSI at idle (system dependent)
- OE Part Number: 4988747
- Replaces: 3936316, 3936317
- Cross-Refs (identification): 4944710, Bosch 0 440 020 047
Often Paired With
- Mounting gasket: 3939258 (’89–’98)
- Spacer plate: 3914284 (’94–’98)
- Fuel supply/return banjo hardware: 3924725 (14 mm banjo bolt)
- Fuel filter service: replace filter and prime with the hand primer after install
What’s In The Box
- (1) Genuine Cummins Mechanical Fuel Transfer Lift Pump (4988747)
- Gasket, spacer, and hardware sold separately (see “Often Paired With”).
Installation Tips
- Use new gasket and confirm spacer orientation; torque fasteners to factory spec.
- Prime the system with the hand primer until firm; check for leaks on warm-up.
- Verify supply pressure and address restrictions (filter, lines) if pressure is low.
FAQ
WILL THIS FIT MY 1994–1998 12-VALVE CUMMINS RAM?
Yes—4988747 is the OE cam-driven transfer (lift) pump for 1994–1998 5.9L 12V trucks with the P7100 injection pump (confirm by VIN/ESN).
IS THIS THE PUMP WITH THE HAND PRIMER?
Yes—this piston-style pump includes a top-mounted hand primer for easy priming after service.
DO I NEED A SPACER OR GASKET?
Yes—use spacer 3914284 (’94–’98) and mounting gasket 3939258 (’89–’98). Replace hardware/seals as needed.
WHAT PRESSURE SHOULD I SEE?
Healthy systems typically show about 25–35 PSI at idle. Verify with a gauge at the P7100 inlet.
WILL THIS WORK ON 1998.5–2002 24V OR 2003+ TRUCKS?
No—those platforms use different (mostly electric or common-rail) lift systems. Order the correct pump for VP44 or common-rail engines.
IS THIS A GENUINE CUMMINS PART?
Yes—OE Cummins 4988747 for proper fit and durability.
